а) (5,2 - 3 1/3) : 1 1/3 = 1,4
1) 5,2 - 3 1/3 = 52/10 - 10/3 = (156 - 100)/30=56/30=28/15
2) 28/15 : 1 1/3 = 28/15 : 4/3 = 28/15 * 3/4 = 7/5=1,4
б) (3/8 + 2 1/7 * 1 1/20) * 1 1/3 = 3,5
1) 2 1/7 * 1 1/20 = 15/7 * 21/20 = 9/4
2) 3/8 + 9/4 = (3+18)/8 = 21/8
3) 21/8 * 1 1/3 = 21/8 * 4/3 = 7/2 = 3,5
в) -2 1/3 + 5 1/7 = -7/3 + 36/7 = (-49 + 108)/21 = 59/21 = 2 17/21
2.a) 2,4 : x = 4,5 : 30
х = 2,4 * 30 : 4,5
х= 16
б) -y - 1 2/3 = 2 1/6
-у = 2 1/6 + 1 2/3
Расчёты: 2 1/6 + 1 2/3 = 13/6 + 5/3 = (13+10)/6 = 23/6 = 3 5/6
-у = 3 5/6
у = - 3 5/6